TED Fellows

Someday, solar panels may be light and cheap enough that they could be hung on a clothesline, thanks to a synthetic mineral called perovskite. Physicist Sam Stranks explains the solar-powered science and the challenges that stand in its way.

In an annual event called Meet to Sleep, women come together to doze in public spaces. These sleep-ins are all about rejecting a culture of fear and harassment and creating one of trust and shared safety, says artist and activist Jasmeen Patheja.

Turn it into a game, says technologist Esra’a Al Shafei. Thanks to features like a point system and a leaderboard, her small site for LGBTQ people in the Arab world is not only fun to use — it’s free from harassers.